diff options
Diffstat (limited to 'arch/h8300/include')
| -rw-r--r-- | arch/h8300/include/asm/hash.h | 53 | ||||
| -rw-r--r-- | arch/h8300/include/asm/processor.h | 7 | ||||
| -rw-r--r-- | arch/h8300/include/uapi/asm/unistd.h | 2 |
3 files changed, 55 insertions, 7 deletions
diff --git a/arch/h8300/include/asm/hash.h b/arch/h8300/include/asm/hash.h new file mode 100644 index 000000000..04cfbd2bd --- /dev/null +++ b/arch/h8300/include/asm/hash.h @@ -0,0 +1,53 @@ +#ifndef _ASM_HASH_H +#define _ASM_HASH_H + +/* + * The later H8SX models have a 32x32-bit multiply, but the H8/300H + * and H8S have only 16x16->32. Since it's tolerably compact, this is + * basically an inlined version of the __mulsi3 code. Since the inputs + * are not expected to be small, it's also simplfied by skipping the + * early-out checks. + * + * (Since neither CPU has any multi-bit shift instructions, a + * shift-and-add version is a non-starter.) + * + * TODO: come up with an arch-specific version of the hashing in fs/namei.c, + * since that is heavily dependent on rotates. Which, as mentioned, suck + * horribly on H8. + */ + +#if defined(CONFIG_CPU_H300H) || defined(CONFIG_CPU_H8S) + +#define HAVE_ARCH__HASH_32 1 + +/* + * Multiply by k = 0x61C88647. Fitting this into three registers requires + * one extra instruction, but reducing register pressure will probably + * make that back and then some. + * + * GCC asm note: %e1 is the high half of operand %1, while %f1 is the + * low half. So if %1 is er4, then %e1 is e4 and %f1 is r4. + * + * This has been designed to modify x in place, since that's the most + * common usage, but preserve k, since hash_64() makes two calls in + * quick succession. + */ +static inline u32 __attribute_const__ __hash_32(u32 x) +{ + u32 temp; + + asm( "mov.w %e1,%f0" + "\n mulxu.w %f2,%0" /* klow * xhigh */ + "\n mov.w %f0,%e1" /* The extra instruction */ + "\n mov.w %f1,%f0" + "\n mulxu.w %e2,%0" /* khigh * xlow */ + "\n add.w %e1,%f0" + "\n mulxu.w %f2,%1" /* klow * xlow */ + "\n add.w %f0,%e1" + : "=&r" (temp), "=r" (x) + : "%r" (GOLDEN_RATIO_32), "1" (x)); + return x; +} + +#endif +#endif /* _ASM_HASH_H */ diff --git a/arch/h8300/include/asm/processor.h b/arch/h8300/include/asm/processor.h index 54e3fd83c..111df7397 100644 --- a/arch/h8300/include/asm/processor.h +++ b/arch/h8300/include/asm/processor.h @@ -111,13 +111,6 @@ static inline void release_thread(struct task_struct *dead_task) } /* - * Free current thread data structures etc.. - */ -static inline void exit_thread(void) -{ -} - -/* * Return saved PC of a blocked thread. */ unsigned long thread_saved_pc(struct task_struct *tsk); diff --git a/arch/h8300/include/uapi/asm/unistd.h b/arch/h8300/include/uapi/asm/unistd.h index 7a2eb698d..7dd20ef76 100644 --- a/arch/h8300/include/uapi/asm/unistd.h +++ b/arch/h8300/include/uapi/asm/unistd.h @@ -1,3 +1,5 @@ #define __ARCH_NOMMU +#define __ARCH_WANT_RENAMEAT + #include <asm-generic/unistd.h> |